A knife is sharpened by a whetstone or a wheeled knife sharpening device. However, a user cannot control a sharpening angle and an operating force exactly if using the whetstone to sharpen a knife, and the user will be hurt easily.
The wheeled knife sharpening device contains at least one grinding wheel and a recess for placing a knife and corresponding to the at least one grinding wheel, such that the at least one grinding wheel sharpens the knife. Nevertheless, the wheeled knife sharpening device cannot sharpen the knife sharply after a period of using time.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.